Knocking through.

Best to get SE to look at it, but to get an idea check what walls are directly above. From my experience split bathroom/toilet walls are not, but best to check first before knocking it down. Hard to price something without seeing it, but if it isn't load bearing I'd say a day labour, a breaker and a skip....and a lot of dust. Most of expense will be making good after, tiling, plastering, altering lights etc.

 

I'd be checking if The wall may is supporting another wall, or if joists rely on it for support or hangers/purlins rely on it to transfer loads to the founds

 

"...there are no walls above it in the loft, just joists that run across in the same direction as the wall."

As you clearly suspect, it's almost certain that this ain't structural or supporting.

I will not go as far as saying I am 100% certain, 'cos that would be silly.

But I'm 99.99997% sure.

 

What's the wall made from? Block or studwork?

Either way, once it's down and you look up at the bare, exposed strip at the ceiling, then you will know for certain.

Actually, can you tell where the wall is from up in the loft? Can you post a photo of this?

 

I've just done this in a bungalow renovation, check where the timbers supporting the roof sit and most likely the wall is built on the floor boards as is often the case in older properties. You could acro the joists above as a precaution. In bungalows non load bearing walls are often a bit narrower than the structural walls. Blocking up can be a pain of it was built out of 3" wide blocks, if this is the case use a timber frame.

 

When you have solid internal walls, even though they may not be supporting things above they may be forming a buttress effect on the external wall at 90 degrees. Much like putting in piers in garden or garage walls

 

Sounds like you are planning to have fun ....

 

Your joists are running parallel to your walls so looks like you can get your sledge hammer warmed up!

 

Ha ha...yep, the joys of DIY. Keep the job tidy and she'll be ok...ish
Reg extractor, can't think of a reason not too other than being vertical, you may get a bit of rain come down the pipe depending on the vent at the top.

 

Are you really planning to use a sledgie for this? Don't you have an SDS drill with a chisel bit - just tackle the mortar joints?


Anyhoo, enjoy...

Now't wrong with using the existing vent pipe for your extractor, with CGN's proviso. Does it have a rain cowl - probably not. Can you get up there to fit one?

Another source of water will be condensation if extracting from a shower or bath - the steam will condense in the cold vent pipe and come trickling back down to zap your extractor fan.

Not sure what the solution is - tho' I'm sure there are plenty. Would an in-line extractor help (not sure why it should!)?

I think having it on over-run for a few minutes when showers and baths have been run would be good - give it plenty time to dry oot yer pipes.